Prep the basics: Line two baking sheets with parchment paper. Set the oven to 350°F (175°C). If your kitchen is warm, chill the chocolate chips for 10 minutes so they don’t melt into the dough.

Cream the fat and sugars: In a large bowl, beat the coconut oil (or vegan butter), granulated sugar, and brown sugar until creamy and well combined, about 2 minutes. The mixture should look slightly fluffy.

Add liquids: Mix in the non-dairy milk and vanilla. It may look a little separated at first; keep mixing until smooth.

Combine dry ingredients: In a separate bowl, whisk the flour, cornstarch, baking soda, baking powder, and salt.

Make the dough: Add the dry ingredients to the wet mixture and stir until just combined. Do not overmix. Fold in the chocolate chips.

Chill briefly: Cover the bowl and refrigerate the dough for 20–30 minutes. This helps control spread and improves chewiness.

Portion: Scoop 1.5-tablespoon mounds (about a heaping tablespoon) onto the lined sheets, spacing 2 inches apart. For thicker cookies, roll into balls. For more spread, leave as scoops.

Bake: Bake for 9–12 minutes, until the edges are set and lightly golden but the centers still look soft and slightly underdone. Rotate the trays halfway for even baking.

Tap and finish: If you like crinkly edges, tap the tray on the counter once after removing from the oven. Sprinkle with flaky sea salt if using.

Cool: Let cookies cool on the tray for 5 minutes, then move to a rack. They’ll firm up as they cool while staying chewy inside.